Figure 1

Indirubins inhibit centriole overduplication in breast cancer cell lines. (A) Immunofluorescence microscopic analysis of HCC1806 breast cancer cells for centrin to visualize normal centrioles (top panels) in contrast to centriole overduplication (bottom panels). Nuclei stained with DAPI. Scale bar indicates 10 μm. (B, C) Quantification of the proportion of HCC1806 or MCF-7 cells manipulated to stably express empty vector (MCF-7/neo) or cyclin E (MCF-7/cyclin E) with aberrant centriole numbers (>4 per cell) after treatment with 0.1% DMSO as solvent control or 1 μM indirubin-3'-oxime (IO), 1 μM 1-methyl-indirubin-3'-oxime (MeIO), 1 μM 6-bromo-indirubin-3'-oxime (BIO), 1 μM 1-methyl-6-bromo-indirubin-3'-oxime (MeBIO) or 1 μM 6-bromo-indirubin-3'-acetoxime (BIA) for 24 h. Each bar represents mean and standard error of at least three independent experiments with a minimum of 50 cells counted per experiment. Only mononucleated cells were assessed for centriole aberrations to exclude polyploid or otherwise altered cells.